The automated production lines of the prior art handle workpieces which are the same shape, contour and dimension. Edges, holes, lugs, keys, depressions, detents, etc. are on the workpieces to provide interlocking positioning and/or gripping means so that identical workpieces may be identically located at work stations. The lines of the prior art reject workpieces which are not the same shape and dimension, and which vary in position and grip means. In other words, the prior art does not tolerate varying shape, contour and dimension, whereas the present invention provides facility for handling workpieces of varying shape, contour and dimension.